α,ω-Diiodoperfluoroalkanes (e.g., I(CF2)nI where n=3-11) are typically expensive and difficult to obtain in large quantity. For example, α,ω-diiodooctafluorobutane can be prepared from tetrafluoroethylene (TFE) and iodine (I2) by the reactions of iodine addition and telomerization. However, the intermediate material 1,2-diiodotetrafluoroethane (C2) is toxic, and tetratluoroethylene is difficult to handle because of its reactivity. Diiododifluoromethane is likewise hazardous. It would be desirable to have methods of making α,ω-diiodoperfluoroalkanes in high yield and/or with little or no C1 and C2 homologous side products.